Pump



Jan. 1, 1946. c. F. DAVIS 2,392,029

PUMP

Filed on. 16, 1943 3 Sheets-Sheet 1 25 ZmzremZmr C4. up E 0/? W6.

Jan. I, 1946. c. F. DAVIS 2,392,029

PUMP

Filed Oct. 16, 1943 3 Sheets-Sheet 2 I I8 17 m /6 I x 1 29 v T Y HYEZ22:71

Patented Jan. 1, 1946 UNITED STATES PATENT orrlcs PUMP Claud F. Davis,Johnson City, Tenn. Application October 16, 1943, Serial No. 506,470

'7 Claims.

My invention relates to rotary hydraulic pumps of the type comprisingconcentric stationary androtor elements defining a plurality ofsegmental cylinder spaces or working chambers separated by bladesshiftable radially in the stationary element.

An important object of the invention is to construct a pump of this typefor eight cycle operation per revolution with a minimum amount of fluidimpulse action and with continuous uniform discharge.

A further object is to produce a pump structure in which the stationaryand rotor elements define a plurality of outer and innersegmental.cylinder spaces or working chambers with only one set ofblades serving both th outer and the inner chambers.

A further object is to provide improved inlet and outlet portingarrangement for the outer and inner cylinder chambers and with the rotorelement functioning as a valve for cooperating with the blades tocontrol the ports for the inlet and outlet flow to and from the cylinderchambers.

Another object is to use blades in the form of cylinders or rollers, andto provide a structure in which the stationary and rotor elements aresymmetrical around a common axis in order to produce perfect balance andeliminate vibration and reduce wear to a minimum.

The above enumerated and other features of my invention are embodied inth structures shown on the drawings, in which Figure 1 is a plan view ofthe pump structure with the rotor housing removed;

Figure 2 is a section on plane II-II of Figure 1 with the rotor housingin place;

Figure 3 is an underside view of the rotary element;

Figure 4 is a plan view of the stationary element:

Figure 5 is a section on plane V-V of Figure 2 with the housing removedand showing the rotary element in on position; and

Figure 6 is a view similar to Figure 5 showing the rotary member rotated90 from its position on Figure 5.

The pump structure shown is adapted to be mounted with its axisvertical, and it comprises the stationary element or base I 0 having theupstanding circular flange II and the circular .wall I! rising therefromconcentric with the flange II. The top side of the stationary .elementl0 provides the seating and bearing surface l3 for the rotary element H.The body I! of the rotary element is cylindrical and seats with itsbottom against the surface i3 of the stationary element concentric withthe flange I I.

The body l5 of the rotary element has therein th elliptical channel Itwhich receives the circular wall I 2 and is coaxial therewith. Thechannel divides the rotor body l5 into outer and inner heads l1 and I8,respectively, the outer head defining the outer elliptical surface a: ofth channel l6 and the inner head defining the inner elliptical surface 1of the channel, the surfaces being parallel so that th channel is ofuniform width throughout. The major axis of the inner head l8 fits theinner diameter of the circular wall I 2 while the minor axis of theouter nead l'l fits the outer diameter of the circular wall so that thinner head at the ends of its major axis engages at all times the innerside of the circular wallwhile the outer head at the ends of its minoraxis engages at all times against the outer side of the circular wall.

The circular wall l2 has a pair of diametrically opposite radial slotsl9 and 20 therethrough for the blades 2| and 22. These blades areprefer-. ably in the form of cylinders or rollers whose diameter isequal to th width of the slots and the width of the channel It, theblades being of a length to extend the full depth of the channel betweenthe surface l3 on the stationary element In and the top of the channel.During operation of the structure, the circular wall I! and the bladesdivide the channel It into four outer segmental cylinder spaces a, b, cand d, Figure 5, and four inner segmental cylinder spaces e, f, g and h,Figure 6. The cylinder spaces are of extent and, with inlet and outletporting arrangement to be described hereinafter, the eight cylinderspaces will sequentially have oil drawn thereto and discharged therefromwith the entire flow through the pump distributed through the eightcylinder spaces or working chambers to produce eight cycle operation.

Describing now the porting arrangement, inlet and outlet ports 1' and oare located respectively adjacent to the outer ends of the oppositesides of the slots '9 and 20, these ports serving the outer cylinderspaces a, b, c and d. Inlet ports 1' and 0' adjacent to the inner endsof the opposite sides of the slots 19 and 20 serve the inner cylinderspaces 6, f, g and h. The location of these ports is clearly shown OnFigure 4, the ports being in the stationary element I0 and terminatingat their upper ends in the bearing face II of the stationary memberwhich is engaged by the rotor member I. As indicated by the dotted lineson Figure 4, and full lines on Figure 2, the inlet ports adjacent to theslots I3 and 20 are in communication with passageways 23 and 23' whichextend from aninlet chamber 24 in the stationary element Ill. an inletpassageway 23 through the stationary element connecting the chamber witha source of fluid such as oil. The outlet ports and 0' at the slots [3and 20 are connected by passageways 26 and 26' with a discharge chamber21 in the stationary element I0, this chamber being shown in Figure 2 asbeing above the inlet chamber 24, these chambers being concentric withthe stationary element.

The stationary element ID has in its upper side the cylindrical bearingrecess 28 for receiving the bearing boss 29 on the rotor element i4. Apassageway 30 extends from the discharge chamber 21 to the bottom of thebearing recess 23 for communication with the discharge bore 3| throughthe body I! of the rotor element and ,the shaft 32 extending therefrom.This shaft may be connected with a suitable driving motor for the rotorelement l4.

' When the rotor element I4 is rotated, the blade cylinders 2| and 22will be engaged by the outer and inner elliptical walls a: and 1/ of thechannel II to be moved back and forth in the slots i9 the space 40.

and 20 in the circular wall I 2 of the stationary element, the bladecylinders at their lower ends moving back and forth between the inletand outlet ports 1, i and o, 0', respectively. As shown on Figure 5,when the major axis of the elliptical channel i6 is in alignment withthe slots l3 and 20, the blade cylinders will be at the outer ends ofthe slots to be interposed between the respective outer inlet and outletports 1' and 0, while the inner inlet and outlet ports 1" and 0' will becovered by the inner elliptical head i8. As shown on Figure 6, when theminor axis of the elliptical channel I6 is in alignment with the slotsl9 and 20, the blade cylinders will be at the inner ends of the slots tobe interposed between the inner inlet and outlet ports 1''. 0', whilethe outer inlet and outlet ports 1 and 0 will be covered by the outerhead ll of the rotor element. Thus, the outer and inner heads I! and I3of the rotor element will function as valves to cooperate with the bladecylinders to prevent direct connection between inlet and outlet portsand to control the ports for the proper sequential flow of fluid intothe various cylinder space or working chambers and the outflow ordischarge therefrom. With the arrangement shown, as the rotor elementrotates, the fluid will be drawn in through the inlet 25 to the inletchamber, 24 and from there through the exposed inlet ports into thecorresponding working chambers for discharge from these chambers throughthe exposed outlet ports to the outlet or discharge chamber 21 and fromthere upwardly through the bore 3| of the shaft 32.

The rotor element is enclosed by a cylindrical cup shape housing 33having the shoulder 34 for seating against the flange Ii, and having theflange 35 threading on to the stationary element III. A bearing member36 in the recess 28 receives the boss 32. A neck 31 extends up from thehousing 33 to receive the shaft 32, and this neck has the inner flange38 between which and the rotor body a bearing member 33 is interposed.

When the housing 33 is applied, the rotor element will be held to thesurface l3 of the stationary element iii. -A look screw 53 is providedfor the housing.

When the pump is operating under heavy pressure, oil may escape outbetween the rotor and the surface i3, and clearance space 40 istherefore provided between the rotor and the housing 33 and flange Iiinto which the escaping oil may flow to exert pressure down against therotor to counteract and balance any upward pressure and thus keep therotor seated.

A gland nut 4| threads into the outer end of the housing neck 31 forcompressing packing 42 around the shaft 32 to seal against leakage fromOn Figure 2 a passage 43 is shown extending laterally from the outletpassages 26' through the stationary element to the exterior thereof, aplug 44 closing the passage end. It may be desirable to discharge theoil from the side of the stationary element instead of upwardly throughthe shaft 32. In such case, the plug 44 would be withdrawn, and theouter end of the shaft would be plugged or a solid shaft would be used.

All the parts of the pump structure being coaxial and symmetrical,vibration is eliminated and perfectly balanced operation results. Theblade cylinders have only line contact with the sides of their guideslots and with the elliptical surfaces of the channel i6, and arefurthermore bathed at all times in oil, so that the movement of theblades is practically without friction. The bearing surface between therotor and stationary element is also kept supplied with oil so that thefriction of operation of the structure and consequential wear is reducedto a minimum. The structure comprises a minimum number of parts whichare of simple shapes and can be economically manufactured and assembled.

I have disclosed a practical and efllcient embodiment of my inventionbut I do not desire to be limited except by the appended claims to theexact construction, arrangement or operation shown and described aschanges and modifications may be made without departing from the scopeof the invention.

I claim as follows:

l. A pump comprising a rotor element having an outer annular memberpresenting an elliptical terminating adjacent to said slots in the pathsof portions of said rotor members whereby said rotor members willfunction as valves to control the connections of said inlet and outletpassageways with said working chambers, said blade elements functioningto prevent direct connection between said inlet and outlet passageways.

2. A pump comprising two relatively rotatable elements, one of saidelements having an elliptical channel therein of uniform widththroughout, the other element having a circular wall thereon engaging insaid channel to divide said channel into inner and outerworkingchambers, said wall having radial slots therethrough, inlet andoutlet ports for said working chambers located in said other elementadjacent to said slots. and blade members in the form of cylindricalrollers movable radially in said slots by the engageelements having acircular wall engaging in said channel to divide said channel into innerand outer cylinder spaces, said wall having diametrally opposite radialslots therethrough, inlet and outlet ports in said second element forsaid outer cylinder spaces disposed at the opposite sides of said slotsadjacent the outer ends thereof and inlet and outlet ports in saidsecond element for said inner cylinder spaces disposed at opposite sidesof said slots at the inner ends thereof, blade members in said slotsextending across said chan' nel to be radially shifted in said slotsupon relative rotation of said elements to be interposed between theinner and outer inlet and outlet ports respectively, said inlet andoutlet ports being in the paths of portions of said first element to besequentially opened and closed thereby, whereby said first element willfunction as a valve to control the sequential connection of said portswith said cylinder spaces.

4. A pump comprising a stationary element having a bearing surface, arotor element seating on said bearing surface for rotation thereon, saidrotor element having an elliptical channel therein of equal widththroughout withits axis coincident with the rotation axis, saidstationary element having a circular wall projecting therefrom into saidchannel concentric with the rotation axis, said wall having twodiametrally opposed radial slots therethrough, blades in said slotsextending across said channel to be shifted radially in said slots bythe elliptical surfaces of said channel when said rotor element isrotated, said wall and said blades during rotation of the rotor elementdividing said channel into inner and outer cylinder chambers, inlet andoutlet passageways in said stationary element, inlet and outlet portsextending from said passageways and terminating in said bearing surfaceinside of said wall adjacent to the inner ends of said slots forconnection with the inner cylinder chambers,

and inlet and outlet ports extending from said passageways andterminating in said bearing surface outside of said wall adjacent to theouter ends of said slots for connection with the outer cylinderchambers, said blades functioning to prevent direct communicationbetween inlet and outlet ports, said inlet and outlet ports being in thepaths of portions of said rotor element whereby said rotor element willfunction as a valve to control the sequential connection of said inletand outlet ports with the inner and outer cylinder spaces.

5. A pump comprising a stationary element having a fiat bearing surface,a rotor element seating on said bearing surface for rotation thereon,said rotor element comprising inner and outer elliptical portions spacedradially to define therebetween an elliptical channel, said stationaryelement having a circular wall projecting from said bearing surfaceintosaid channel, said wall having slots therethrough, blades in saidslots extending across said channel to be shifted radially by theelliptical surfaces of said channel when said rotor element is rotated,said wall and blades dividing said channel into inner and outerhydraulic cylinder chambers, and inlet and outlet ports for saidchambers all terminating in the plane of said bearing surface in thepaths of said rotor element portions to be progressively overlapped bysaid rotor element portions, whereby said portions will function asslide valves to control the sequential connection of said ports withsaid cylinder chambers.

6. A pump comprising two relatively rotatable elements having bearingfaces engaging in a bearing plane, one of said elements having anelliptical channel therein, the other element having a circular wallthereon engaging in said channel and dividing said channel into innerand outer working chambers, said wall having radial slots therethrough,inlet and outlet ports for said working chambers located in said otherelement adjacent to said slots, and cylindrical blade members movableradially in said slots and functioning to prevent direct connectionbetween said inlet and outlet ports, said inlet and outlet ports allterminating in said bearing plane in the paths of portions of said oneelement whereby said one element will function as a slide valve tocontrol the connection of said inlet and outlet ports with said workingchambers during relative rotation of said elements.

7. A pump comprising relatively rotatable concentric elements havingfiat bearing faces in bearing engagement with each other, one of saidelements having an elliptical channel therein concentric with saidelement, said other. element having a circular wall projecting therefrominto said channel and having radial slots, cylindrical blades in saidslots for radial movement therein during relative rotation of saidelements, said circular wall and said blades dividing said channel intoa plurality of inner and outer hydraulic chambers, and inlet and outletports in said other element communicating with said channel and allterminating in the bearing face of said other element in the paths ofportions of said one element, whereby, during relative rotation of saidelements, said one element will function as a slide valve for said portsto control the sequential connection thereof with said inner and outerhydraulic chambers.

CLAUD F. DAVIS.

